It's a very tough statement, which casts quite a broad net when talking about "crimes against humanity." Here's the opening paragraph:

"In accordance with the Resolutions of the United Nations and the World Health Assembly, the 2015 Vatican Summit of Mayors from the major cities of the world, the 2014 Joint Declaration of faith leaders against modern slavery, and the Magisterium of Pope Francis, who in June 2016, at the Judges’ Summit on Human Trafficking and Organized Crime, stated that organ trafficking and human trafficking for the purpose of organ removal are “true crimes against humanity [that] need to be recognized as such by all religious, political and social leaders, and by national and international legislation,” we, the undersigned participants of the Pontifical Academy of Sciences Summit on Organ Trafficking, resolve to combat these crimes against humanity through comprehensive efforts that involve all stakeholders around the world."Here's the paragraph defining what those crimes against humanity are, which to my eye seems to conflate three very different things. It is number 1 in their list of recommendations."That all nations and all cultures recognize human trafficking for the purpose of organ removal and organ trafficking, which include the use of organs from executed prisoners and payments to donors or the next of kin of deceased donors, as crimes that should be condemned worldwide and legally prosecuted at the national and international level."That is, if I read the full statement correctly (you should read it yourself), they are proposing that

taking organs from executed prisoners,

making payments to living donors, and

making payments to next of kin of deceased donors

should all be considered crimes against humanity. Incidentally, the phrase "crimes against humanity" is one that I hear most often in the context of genocide, although I recognize that it is also used for other horrific crimes that target populations.I am not encouraged that this will lead to a sensible discussion about either incentives for donation or (even) removing financial disincentives.